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### Course: MAP Recommended Practice>Unit 35

Lesson 11: Comparing negative numbers

# Negative numbers, variables, number line

Given a, b, and c shown on the number line, Sal determines if statements like -b < c are true.

## Want to join the conversation?

• who invented math exactly??
• People to answer this question can not be 100% certain that they are correct. It goes back MILLIONS of years
• Normally, to the left of the zero are negative numbers and to the right of the zero are positive numbers in number line, now how a negative number can be to the right of the zero. !
• I am a bit confused to your question but a negative number can never be to the right of the zero.
• I am confused on this whole lesson.
• Can you make a video just like this but with numbers? For me it was kind of confusing with the letters. Thank you!
• The letters are variables, meaning numbers in disguise, so to say. They can have ever changing values.
• i do not understand werent negative no.s to the left of zero?
• so -a is the opposite of +a, and if the +a was on the left of the number line, then -a will on the right of the nuber line?
• Yes, -a is on the other side of 0
• This could be explained better. It does not address the natural confusion that arises of why letters are numbers and why items to the left of zero are not negative.
(1 vote)
• The letters are called "variables." These variables are usually used as a substitute for an unknown number. Items to the left of zero are negative. For example, b could be representing -1. But, when it asks for negative b, then my example's negative b would be --1. --1 then becomes +1 or just 1 since the two negatives cancel out. Let me know if this is still hard to understand!
• Normally, to the left of the zero are negative numbers and to the right of the zero are positive numbers in number line, now how a negative number can be to the right of the zero. !